Pressure cooker with selectively adjustable vent valve



1952 G. c. WYMAN 2,614,724

PRESSURE coom um suscrxvmv ADJUSTABLE van-r VALVE Filed lay 13, 1948 5Sheet's-Sheet 1 G CW 2 80 1434 w figi Oct. 21, 1952 G. c.

PRESSURE COOKER WITH SELE Filed May 15, 1948 5 sheets-suede /%AA M\I.,/// n3 inven azmn c.

PRESSURE COOKER WITH SELECTIVELY ADJUSTABLE VENT VALVE Filed May 15,1948 G. c. WYMAN Oct. 21, 1952 5 Sheets-Sheet 5 Iii/71611302: (Jenn Cfhymn/n (7M WV och 1952 G. c. WYMAN 2,614,724

I PRESSURE COOKER WITH sELEcTIvELY ADJIjSTABLE VENT VALVE Filed lay 13,1948 5 Sheets-Sheet 4 J 7/ I v E3 lnveni'oz":

azenn 6T Wy man,

EL MWWv Oct. 21, 1952 e. c. WYMAN 2,614,724

PRESSURE COOKER WITH SELECTIVELY ADJUSTABLE VENT VALVE Filed May 13,1948 5 Sheets-Sheet 5 Z 171126217302. 6 enn 61W man.

(Hf/figs the lines I ll I Patented Oct. 21, 1952 PRESSURECOOKER WITHSELECTIVELY ADJUSTABLE VENT VALVE Glenn Wyman, Rome, N. Y., assignor toRevere Copper-and Brasslncprporated, RomaN. Y., a corpor'ation ofMaryland Application May '13, 1948, Serial No. 26,862

My invention relates to pressure cookers. I The invention hasamongitsobjects improved means for ,controlling the pressure within thepressure cooker. and for preventing release of the cover when the cookeris under pressure. The above and, other objects of the'invention will'be best understood from the following description when read in thelight of the accompanying drawings of a specific embodiment of theinvention selected for illustrative purposes, while the scope of theinvention will be more particularly pointed out in the appended claims.1

In the. drawings: Fig. 1 isa plan of a pressure cooker according to theinvention; a

" Fig.'2 is a=side elevation of a pressure cooker according'to-Fig. 1;with parts 111880131011;- 7 -Fig. 3- is a section on-the line 33-- ofFig.4, on an enlarged scale, of a fragment of the weights forcontrolling the pressure relief valve; r Fig. 4 is a plan of a fragmentof Fig. 1, on an enlarged scale; w i

. Fig. 5' is an isometric view of a part employed in the cookeraccording tothepreceding figures; Fig. 6 vis a section on the line 6-6,of Fig. 4; Fig. 7 is asection on the;line'1-'l of Fig.6 showing adetail; Fig. 8 is a section onthe line 8--8 of Fig. 6; I Figs; 9 and 10are, respectively, sections corresponding to. Fig. 6, with the parts indifferent operative. positions; v

"Figs. 11 and 12 are, respectively, sections on and l2-.l2 of Fig. 4,with parts omitted;; I ::m -Fig'113 is a plan of the uppervalvecontrolling weight of Fig. 6; V a -Fig.'14: isa side elevation of. theweight according to Fig. 6; v Fig. 15 is a plan of. the middlevalve'controlling weight'according to Fig.6;

16 is a side elevation of the weight according to Fig. 15; i

Fig. 1'7 is a side elevation of the lower valve controlling weightaccording to Fig. 6; and 4 Fig. l8-is a side elevation of the weightaccordingto Fig. 17. The pressure cooker illustrated by the drawingscomprises a container, preferably formed of sheet metal such asstainless steel, having abottom walll and cylindrical side walls 3.Adjacent their upper edges the side walls are formed to present anoutwardly flared frusto-conical portion 5 extending entirely about saidwalls. At its-upper edge this frusto-conical portion is formed topresent an inwardlyturnedtlip 1 extending "about said portionv forapproximately At the side of the frusto-conical portion diametricallyopposite the lip 1 said portion is formed with an outwardly projectingdownwardly turned lip 9 of shorter angular extent thanthe lip 1. Midwayits length thelip' 9 is. shown as formed with a notch l l (Figs. iand6). Carried by the container is a radially projecting handle [3 havingabase portion l5 secured to the cylindrical wall of the container,preferably by welding, this handle being provided with the handle gripsAs shown, the cover, which also is formed of sheet metal, preferablystainless steel, is shaped tov present a dome-like central portion l9surrounded by a'flattened relatively narrowannular flange 2|. Integralwith the' outer peripheral edge of thisflange is an inwardly turneddownwardly extending frusto-conical flange 23 extending-entirely aboutthe cover.- Carried by the cover at itsunder side is'a gasket ring 25 ofgreater height than the flange 23, this ring being formed of flexiblematerial, ,such as synthetic rubber, and being shaped to fit into'thespace between the flanges 2land 23 and to provide a lower portion 21which-projects radially beyond the outer side of the flange 23 at itslower edge so as to-bear uninterruptedly against the inner wall of thefrusto-conical portion 5 of the container when the cover is assembledwith the latter. :As shown, the cover is provided with a radiallyprojecting handle 29 provided with the'handle grips 3|. 'I'his handle isprovided with a base portion 33 which and the adjacent portion of thehandle-conform to theupper sides of the dome-shapedportion I9and-annular flange 2| of the cover to which they are secured preferablyby welding. Secured tothe under side of the handle 29, preferably bywelding, is the base 35 of a strip-like member which, at its endadjacent the cover, is provided with a downturned portion 31, whichlatter, .at its lower end, is upwardlyv turned to form a book 39. I

When the parts are in the position shown by the drawings the cover isretained on the container by the container lip 1 positioned above. thecover flange 2| and by the container lip 9 'posi tioned above the coverhook 39. When the cover is initially placed on the container aclearance43 exists between the container lip -'l a nd'cover flange 2|, and anequal clearance 45 between the container lip'9 and cover hook '39, theprojecting portion. 2.! of the gasket ring 25' bearing against thefrusto-conical container portion so as to seal the joint between thecover and cone 3 tainer and thus permit pressure to build up in thecooker. When the pressure builds up the cover rises to take up theclearances 43 and 45, the gasket due to its resiliency and the pressurein the cooker remaining in contact with the frusto-conical containerportion 5 so that at all times the gasket renders the joint between thecover and the container steam-tight.

As shown, the base portion 33 of the handle and cover portion I9immediately below it are formed with a screw-threaded perforation (Fig.6) in which is received the screw-thread ed shank 49 of a metal screwplug having a head 5I at the under side of "the cover.

As shown, the portion of the under side ofthe cover surrounding theperforation 41 is recessed at 53 to receive a resilient annular gasketWasher 55 interposed between the bottom of said recess and the adjacentside of the head 5I for rendering the joint between the plug and thecover fluid-tight. As shown, the plug is formed with a through passage5'! forming a vent for the cooker. The upper peripheral edge 59 of thispassage cooperateswith a frusto-conical valve SI for controlling suchvent.

A's shown,'the cover handle 29 adjacent the baseportion 33 thereof ateach of its opposite sides is provided with an upstanding ear 63, eachof these ears having a perforation 65 (Fig. '12).

Supported by these ears is a pin 61 the opposite spaced tabs '13projecting toward the other ear.

Each end-piece is shown as provided with aperforation I5 of slightlysmaller diameter than the perforation in the ear, as clearly indicatedin Fig. 12. The clip is applied to the ears by forc ing it over them sothat the end-pieces heat the outer sides of the ears with the adjacentportions of the bridge-piece II and the tabs I3 engaging the oppositevertical edges of the ears,

respectively. The pin is provided with rounded ends 'II projectingbeyond the outer surfaces of the end-pieces 69 of the clip so that whenthe clip is forced'over'the ears the end-pieces will resiliently bend tocause these rounded ends of the pin to snap into the perforations '55 ofthe end-pieces, as 'clearly shown in Figs. 4 and '8. In this way the pinholds the clip against removalfrom the ears, while the clip holds thepin in the perforations of the ears. By removing the clip, which may bereadily done because of its resiliency, the pin may be slid longitudinally for removing it from the ears. Swingingly mounted on the pin 61 are aplurality of weights for controlling the "vent valve 6|. As shown, threeof these weights 'are provided, a lower weight I9, an intermediateweight. 7

8i, andupper weight 83. As best illustrated by Figs. 4, 6, 8, and .13 to18, these weights are in the form of flat disks. Thelower "weight .19,'asshown, is providedat one peripheral side'thereof with a pair ofspaced laterally projecting upwardly extending lugs each of which isprovided with a perforation 81 through which the pin '61 extends, theouter. sides 89 of these lugs being in closelyadj acent relation totheopposite III.

sides of the ears I53 so as to minimize any lost motion of the weightlongitudinally of the pin. The intermediate weight 8 I, as shown, isprovided at one peripheral side thereof with a pair of spaced laterallyprojecting downwardly extending lugs 9I each of which is provided with aperforation 93 through which the pin "6! "extends. 'These lugs 9| arereceived between "the lugs 85 of the lower weight I9, the outer sides 95of the lugs 9I being in closely adjacent relation to the inner sides -91of the lugs 85 of the lower weight '19. The upper weight 83 is shown asprovided at one peripheral side thereof with a laterally projectingdownwardly extending lug 99 provided withaperforation IIlI through whichthe pin 61 extends, the outer sides I03 of the lug 99 being in closelyadjacent relation to the inner weight 7 9 is provided'with anaxial'through opening I97 'form'ed adjacent the under side of the weightwith aredu'c'ed diameter portion I09 '50 to provide an upwardly fac'ingshoulder. I II. The frusto-conical portion of the vent valvetl at itsbase is formed with an annular flange I I3 adapted, when the parts arein thepos'ition shown by Fig. 6, to rest on the under surface portion ofthe weight surrounding the reduceddiam'eter portion I09 of theopening'in the latter.- .Rearwardly of the flange I3 the valvehas ashank II5 extending into the reduced diameter portion I99 of the openingin the weight. 'This shanki'at its rearward end has a reduced diameterportion III which carries an annular metal washer II9. This washer seatson the shoulder between the reduced 'diame'terportion II! of the-shankand'the body ofthe shank, and is secured tothe reduced diameter portionby riveting over "the projecting -end or that portion asindicat'ed atThe body of the shank is of suchleng'th that, when the parts are in theposition showniby Fig. 6, the washer is spaced from "the-shoulder I I Iof the opening in "the weight, while the diameter of the reduceddiameter portion "I 99 of the opening is-greater than'that of the shank.This con struction permits the valve to slide laterally and to tiltrelative to the weight .19 so as to 'compensate for lost motion of thepivotal support for the weight and discrepancies in manufacture, andthus insures the frusto-oonical-surface of the valve properly seatingonthe peripheral edge '59 of the vent passage 51.

It will be observed that the weight I9 exerts a downward force'tendingto holdthe valve GI on its seat, and that the weights 8i and 83, :in theposition of parts shown'by Fig. 6, augment such downward force; If it isdesired to decrease the force by which the valve is forced downward theupper weight 83 may be moved to the position shown by Fig. 9,"a nd if itis desired still further to decrease that force the intermediate weightmay be movedjto'a similar position, while if it is desired entirely tovent the cooker all the weights may be moved to the position shown byFig. 10. In this way the cooker may be operated under any of threeselected pressures, say 5 pounds per square inch, 10 pounds per squareinch, and 15 pounds per square inch. The weight 83, when swung to itsupward position'shown by Fig. 9, is shown as supported by the upper edgeof the laterally projecting portion 22 of the bridgepiece II of the clipwhich removably holds the pin 67 in place. Successive weights whenraised to their upperpesition rest againstthe weight '83,

' sa e and hence are also supported by the bridge piece. The parts, asshown; are so proportionedthat,

when the weights are swungto their upper positions, the center ofgravity of each of them is at the" side of the pin 6! opposite thecovervent As shown, the several weights arepreferably provided withmeans for readilydetachably seicuring them' together to facilitate theirmanipu- 'lation by the operator. To this end the weight 'l9'at its upperside-is shown as formed with-a recess I23 (Fig. 3) having a reduceddiameter portion I25 so as to provide an upwardly facing shoulder I21;Within this recess is received the flange portion I29 of the socket partI3I of a snap ffas't'ene'r of common' construction, "this flange restingagainst the shoulder I'2'I-and being sefcuredin the recess by headingover the material of the weight at the outer peripheral edge of therecess as indicated at I33. The'snap fastener stud "part I35, whichcoooperates with the socket part I3I of the fastener, is carriedbytheweight .8I, the flange portion I31 of this stud part being--received in a recess I39 at the under side-of the weight 8 I, in whichrecess -it is secured'in the same manner as the socket part of thefastener. In a similar way the upper side of the weight 8 I is pro videdwith a socket part I4I- of a second and like snap fastener, andthe'under side of the weight 83 with a fastener stud part I43cooperating with said socket part, as will be clear from Fig. 3. The

I peripheral portions of the weights 19 and 81 bpposite their pivotalsupport are shown-as provided with notches I45 (Figs. 3,6, and 15 to 18)for facilitating engaging the weights 83 and 8| for pulling the studparts of the snap fasteners carried bythose weights out of thecooperating "socket parts of the snap fasteners carried by the weightimmediately below each of th'emm;

As illustrated, theportion of the cover handle base 33 between the earsE3 isformedon itsupper side with a cylindrical recess I41 (Figs. 6vand.8): j which loosely receives a cylindrical 'lugJI 49 formed integrallywith and projecting. downwardly from the apex portion of a bent or anglelever II-,.-the convex portions I 53 of this lever'at opposite sides 5of the lug I49 swinging or rockably resting o'n the upper surface ofthebase portion 33' of thecover handle. "Ihelever extends radiallyoutwardly of the'cover through a notch I54 formed in the bridge-piece IIof the clip which retains the pivot pin 6'! in position, this notchbeing formedin the portion of the bridge-piecebelow the projece tion I22thereof, asfclearly shownin'Fig; 5.. ,At its outer end the lever I5Iintermediateitswidth carries-a downwardly projecting locking pin I55.This pin projects downwardly throughqand fits the opposite lateral.sides of an elongated slot-like opening I51 (Figs. 6 and 7) formed inabushing.

I59, this bushing being fixedly secured, in;.a through opening I6Iformed in the coverhandle 29. When the parts are in the position shownbyFig. 6 the lower end ofthe pin I55 is received in the notch I I in thelip 9 of the container, and is of sulficient length to be still receivedin such notch when the cover rises because of pressure within the cookerto take up the clearances 43 and 45. Hence, when the parts are in theposition shown by Fig. 6, the cover is prevented from being rotatedrelative to the containerfor releasing the cover therefrom. l As shown,the lower weight I9 is provided with a web I63 (Figs. 8, l7 and .18)integral with the lower portions of the lugs 85 of that weight and theportion of its peripheral edge between them. This web carries aprojecting lug or cam I65 having a curved cam surface I 61. This camsurface is adapted-to cooperate with the upper surface I69 of thetail-piece I'II of the rockable locking lever I5I for raising thelockingpin I55 out of the notch I I in the container lip 9 when thelower weight I9 is swung fromits position shown by Fig. 6 to itsposition shown by Figi 10. When the lower weight is so swung the cookeris vented to relieve the pressure therein, under which conditions thecover may be rotated rela tive to the container to release it therefrom;Preferably, the tail-piece ill of the lever I5I is provided at the underside of its free end with a downwardly extending projection I13 which isin contacting or closely adjacent relation with the upper surface of thebase 33 of the cover handle when the parts are in the position shown byFig. 10 so as to retain the leverin assembled relation with the otherparts when the lower weight is in that position, the cam lug I65 and pinI,55 'being so proportioned as to retain the lever in assembled relationwith the other parts when the weight is in the posi-'- tion shown'byFig. 6;

In operating the cooker, after-the container is charged with food to'becookedthe cover may be placed on the container and secured thereto withall the weights in their raised positions shown by Fig. 10. lhe cover isapplied'to'the container, for securing itthereto, with the cover handle29 out of vertical alignment with the container handle I3 and inclinedslightly upward to such an extent that the edge portion of the coveropposite its handle may be, inserted under the lip I ofthe container.The handle 29 may then be lowered to cause the radially outwardlyprojecting portion 21 of the gasket ring to seat on the frusto-conicalportion 5of the container throughout the angular extentof such ring,whereupon the handle 29 may be swung to bring it into vertical alignmentwith the handle I3 of the container for placingthe hook 39 of the coverunder the hp 9 of the container. This will place the pin I55 'invertical alignment with the notch II in the lip 9 of the container, so

that when the lower weight is moved by the operator from its positionshown by Fig. 10 to thatshown by Fig. 6 the lever I5Iwill b,e.Der-

mitted to swing downwardby gravity tocause the pin I55 to enterthe notchforjpreventing release of the coveruntil-theweights are again swung totheir positionsfshown by Fig. 10. It

-will be observed that the tilting of the cover to insert its edge underthe containerlip I isin such direction thatthe weights will bemaintained in their upper positions so that they will not fall and acttocause the locking ,pin I55 to interfere with the necessary step ofrotating the handle projecting radially therefrom, meansfor locking thecover to the container enforcing positioning of the grip portionsfofsuch two handles in closely adjacent superimposed relation for causingthem tov act conjointly lasfa single handle grip for the cooker, thecoverha'vs ing a vent opening, vent. controlling meansio'r 7 c saidopening comprising .a vent waive adapted to be urged toward openposition by pressure oft-the fluidto be vented and a ventcontrollingweight for urging :said :valve toward closed ,posi tion in opposition tosuch pressure,- one or more auxiliary vent controlling weightsadaptedlto be supported by the first mentioned weight ,Ior augmentingthe valve closing force exerted :by the latter, each of (said weightsbeing operatively mounted on said cover for swinging vabout a horizontalaxis laterally spaced from said openin for selective manual movement to,its vent controlling position, in which ,position the center of gravityof the weight is at the same .sideaof its .axis ofwswinging as saidopening, .or'to a positionin which its center of gravity is :at .theopposite side-of said axis and the weightwthus maintained out of ventcontrolling position, whereby the first mentioned weight .may I becaused exclusively to control escape of fluid through: said opening orthat weight and one or more of said auxiliary weights may be caused tocontrol it or such escape may be. caused .to be uncontrolled by any ofsaid weights, said .vent opening being positioned adjacent the base of.the .coverhandle, said horizontal axis of swingingof each weight beingtransverse to and intersecting the vertical plane which includes thelongitudinal axialllineuof the grip portion of. the cover handle and.bei-ngpositioned between the vent .openingiand such grip portion, thefirst mentioned weight .having an under side of enlarged area which whensaid weight controls said valve is positioned above said vent opening to.act as a shield against upwardly directed steam .from said ventopening, each weight being swingable about its said ,axis of swingingtoward and away from said grip portion of said cover handle for securingtheselected positionsof a rrangement of said weightswthe swingingmovement of the first mentioned weight when swung toward said lastmentioned grip ,portionbeing limited to a position in which said underside of that weight is directed upwardly and interposed between saidventopeningand such grip portion so as to actto shield the latteragainst steam escaping 'fromsaid vent opening.

2. A portable pressure cooker comprising :a container and a covertherefor, each having "a handle projecting radially therefrom,.meansffor locking the cover to thecontainer' enforcing positioning ofthe grip portions of such two handles in closely adjacent superimposedrela tion for causing. them to act conjointly as a single handle gripfor the cooker, the "cover having a vent opening, vent*controlling'means for said opening comprising'a vent valve adapted tobe urged toward open position by' pressure of thefluid to be vented anda'vent controlling weight for urging said valve toward closed positionin opposition to such pressure, one or more auxiliary vent controllingweights adapted to be supported by the first mentionedweightfor'augmenting the valve closing force exerted by the weightis at thesame side of said axis as said opening, or to a position in which itscenter of gravity is at "the opposite side ofsaid axis and theweightthusmaintained out of vent controlling position, whereby thefirst mentionedweight 8 7 may .be causedexclusively to control .escape vof fluidthrough'said opening or that weightand'one or more of said-auxiliaryweights may be caused to control it or such escape may be caused to beuncontrolled by any of said weights, said vent opening being positionedadjacent the base of the cover handle, said horizontal axis of-swingingof each weight being transverse to and intersecting the vertical planewhich 1 includes the longitudinal axial lineof the grip portion of. thecoverhandle and being positioned between the vent opening and such gripportion, the first mentionedv weight :having an under side of enlargedarea which when said weight controls said valve is positioned above saidvent opening to-act as a shield against upwardly directed steamlfromsaid vent opening, each weight being swingable aboutits said axis ofswinging toward and away from said grip portion of said cover handleforsecuring the selected positions of'arrangement or said weights, theswinging movementof the first :mentioned weight when swung toward saidlast mentioned grip-portion being limited toaposition in which saidunder side of that weight isdirected upwardly 'and interposed betweensaid vent opening and suchgrip portion so as to actto shield the latteragainst steam escaping from said vent opening .'3.'The combinationaccording to claim ,1 in Which the valve is carried by the firstmentioned weight of that claim, l I

4. Theqcombination according toclaim 2 in which the valve is carried bythe first mentioned weight ofthat claim.

5. A portable pressure cooker comprising a container and a covertherefor, each having a handle projecting radially therefromgmeans forlocking the cover to "the container. enforcing positioning of the gripportions of .such two handles in closely adjacent superimposed relationfor causing them toract conjointlyas ,a single handle' grip for thecooker, the cover having a vent opening, means for controlling saidopening comprising avalve adapted to be urged toward open positionbypressure of the fluid: to be vented and a weight for urging saidvalve'toward closed position in opposition'to such pressure, whichweight carries said valve, one or more independently movableauxiliaryweights for controlling said opening adapted to be supported by thefirst mentioned weight in superimposed relation thereto for "augmentingthe valve closing force exerted by said'first mentioned weight; meansmounting said weights on the cover for swinging, each about a horizontalaxis laterally spaced from said opening, into selected'positions ofarrangement in which one or moreof said auxiliary weights areunsupported by said first mentioned weight-and the latter is operativeto control said opening or in which all of said weights are inoperativeto control said opening, said vent openingbeing positioned adjacent thebase -of the cover handle, said horizontal axis of swinging of eachweight being transverse to and intersecting the vertical plane whichincludes'the longitudinal axial line of the grip portion of the coverhandle and being positioned'between the vent opening and such gripportion, the first mentioned weight having an under side of enlargedarea which when said weight controls said valve is positioned above saidvent iopeningto act as a shield'against upwardly directed steam fromsaid vent opening,

' each weight being swingable about its said axis of swinging toward andaway from said grip portion of said cover handle for securing theselected positions of arrangement of said weights, the swinging movementof the first mentioned weight when swung toward said last mentioned gripportion being limited to a position in which said under side of thatweight is directed upwardly and interposed between said vent opening andsuch grip portion so as to act to shield the latter against steamescaping from said vent opening.

6. The combination according to claim in which the mounting means forthe weights has a common horizontal axis laterally spaced from the ventopening.

7. The combination with a body having a vent opening of means forcontrolling said opening comprising a valve adapted to be urged towardopen position by pressure of the fluid to be-vented and a weight forurging said valve toward closed position in opposition to such pressure,one or more auxiliary weights adapted to be supported by the firstmentioned weight for augmenting the valve closing force exerted by thelatter, means mounting said weights for independent swinging, each abouta horizontal axis spaced from said opening, and readily engageable andweights to each other whereby to facilitate swinging them as a unit.

8. A pressure cooker having a container portion and a cover therefor,the latter being provided with a vent opening, a valve for control lingsaid opening, a weight for urging said valve toward closed position,which weight overlies said vent opening in relatively closely spacedrelation thereto, one or more auxiliary weights adapted to be supportedon the first mentioned weight for augmenting its closing force on saidvalve, a laterally projecting handle for said cover, each of saidweights being mounted for swinging about a horizontal axis at one sideof said opening adjacent the base of said handle,

an upwardly projecting shield positioned between I said axis and handlefor protecting said handle from steam escaping from said opening to thespace between the cover and the first mentioned weight, said weightsbeing adapted to be swun about said axis to a position in which they areinoperative to control escape of steam through said opening, in whichposition they project upwardly from said axis and rest against and aresupported by said shield.

9. A pressure cooker having a container portion and a cover therefor,the latter being provided with a vent opening, means for securing saidcover to said container portion operated into engaged and releasedpositions by relative rotation of the two, releasable lock forpreventing such relative rotation when the cover is so secured, a valvefor controlling said opening, a weight for urging said valve towardclosed position, one or more auxiliary weights adapted to be supportedon the first mentioned weight for augmenting its closing force on saidvalve, said weights being mounted on the cover for swinging about ahorizontal axis at one side of said opening whereby said weights may beseverally tilted into a position in which they are inoperative tocontrol escape of vapor through said opening, and means operated only bythe first mentioned weight for actuating said look into releasedposition when that weight is so tilted.

10. The combination according to claim 1 in which the valve is carriedby the first mentioned weight of claim 1 and comprises, a free endportion of circular transverse cross-section tapered toward its outerend, which tapered free end portion is adapted to enter the vent openingand laterally coact with the walls of said openin for closing saidopening, said valve and said weight having cooperating portions forsecuring said valve to said weight providing a lost motion connectionbetween them permitting the valve to slide laterally relative to saidweight.

GLENN C. WYMAN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 393,748 Dixon Dec. 4, 1888708,527 Calder Sept. 9, 1902 835,056 Calder Nov. 6, 1906 1,508,696Jacobs Sept. 16, 1924 1,585,512 Roades May 18,- 1926 2,200,903 StephensMay 14, 1940 2,428,483 Wittenberg Oct. '7, 1947 2,436,566 Goldberg Feb.24, 1948

